When defense lawyer Fermín L. Arraiza-Navas sat down with a prospective client in San Juan, Puerto Rico last April, he casually asked the man about the Global Positioning System (GPS) ankle bracelet that he was wearing as a condition for his bail.

Image: Wikimedia Commons.

The reply was just as casual.

“They speak to me through that thing,” the man said.

It wasn’t the first time the lawyer encountered GPS bracelets with apparently extraordinary powers. He told the Puerto Rico Center for Investigative Reporting (CPIPR) that a previous defendant’s GPS ankle bracelet started to vibrate during a meeting with him.

But Arraiza-Navas decided this was more than a coincidence. He cancelled the meeting and filed a motion at the Puerto Rico State Superior Court in San Juan to have the device removed.

During the court hearing on the motion, his worst suspicions were confirmed.

A Corrections Department agent, who works at the Puerto Rico Pretrial Services Office’s monitoring center for defendants free on bail, placed a GPS ankle bracelet on the court podium and made a call from the device to a technician of the SecureAlert company, which provides them at a facility in Sandy, Utah.

The technician, who was addressed through the GPS ankle bracelet—which has a phone feature—testified that, although the device is supposed to vibrate when activated from Utah, the feature could be turned on without warning.